Lottig, Roy A. | Engineering Papers

NASA NTRS1993

Development and use of hydrogen-air torches in an altitude facility

A hydrogen-air ignition torch concept that had been used successfully in two rocket engine test facilities to consume excess hydrogen in their exhausters at atmospheric conditions was experimentally evaluated and developed in an altitude test facility at NASA Lewis Research Center. The idea was to use several of these torches in conjunction with hydrogen detectors and dilution air to prevent excess accumulation of unburned hydrogen or mixtures of hydrogen and air exceeding the sea-level lower flammability limit in the altitude facility exhaust system during hydrogen-fueled propulsion system tests. The torches were evaluated for a range of fuel-to-air ratios from 0.09 to 0.39 and for a range of exit diameters from 19/64 to 49/64 in. From the results of these tests a torch geometry and a fuel-to-air ratio were selected that produced a reasonably sized torch exhaust flame for consumption of unburned hydrogen at altitude pressures from sea level to 4 psia.

Lottig, Roy A.↗

NASA NTRS1993

Development and use of hydrogen-air torches in an altitude facility

A hydrogen-air ignition torch concept that had been used successfully in two rocket engine test facilities to consume excess hydrogen in their exhausters at atmospheric conditions was experimentally evaluated and developed in an altitude test facility at NASA Lewis Research Center. The idea was to use several of these torches in conjunction with hydrogen detectors and dilution air to prevent excess accumulation of unburned hydrogen or mixtures of hydrogen and air exceeding the sea-level lower flammability limit in the altitude facility exhaust system during hydrogen-fueled propulsion system tests. The torches were evaluated for a range of fuel-to-air ratios from 0.09 to 0.39 and for a range of exit diameters from 19/64 to 49/64 in. From the results of these tests a torch geometry and a fuel-to-air ratio were selected that produced a reasonably sized torch exhaust flame for consumption of unburned hydrogen at altitude pressures from sea level to 4 psia.

Lottig, Roy A.↗

NASA NTRS1987

Full-scale thrust reverser testing in an altitude facility

A two-dimensional convergent-divergent exhaust nozzle designed and fabricated by Pratt and Whitney Aircraft was installed on a PW1128 turbofan engine and tested during thrust reverser operation in an altitude facility at NASA Lewis Research Center. A unique collection system was used to capture the thrust reverser exhaust gas and transport it to the primary exhaust collector. Tests were conducted at three flight conditions with varying amounts of thrust reverse at each condition. Some reverser exhaust gas spillage by the collection system was encountered but engine performance was unaffected at all flight conditions tested. Based on the results of this test program, the feasibility of altitude testing of advanced multifunction exhaust nozzle systems has been demonstrated.

Mehalic, Charles M.↗

NASA NTRS1987

Full-scale thrust reverser testing in an altitude facility

A two-dimensional convergent-divergent exhaust nozzle designed and fabricated by Pratt and Whitney Aircraft was installed on a PW1128 turbofan engine and tested during thrust reverser operation in an altitude facility at NASA Lewis Research Center. A unique collection system was used to capture the thrust reverser exhaust gas and transport it to the primary exhaust collector. Tests were conducted at three flight conditions with varying amounts of thrust reverse at each condition. Some reverser exhaust gas spillage by the collection system was encountered but engine performance was unaffected at all flight conditions tested. Based on the results of this test program, the feasibility of altitude testing of advanced multi-function exhaust nozzle systems has been demonstrated.

Mehalic, Charles M.↗